Which of the following best describes the required separation between buried mortars and the wall of troughs or drums?

Which of the following best describes the required separation between buried mortars and the wall of troughs or drums?

• A. 1 inch
• B. 2 inches
• C. 3 inches
• D. 4 inches

Answer: (B)

Two inches is the required separation. This clearance keeps the buried mortar tube from contacting the wall of the trough or drum, reducing the chance that the blast or fragments transfer energy directly to the container. It helps contain debris, minimizes heat transfer to the trough wall, and accommodates minor shifts during burial. One inch would be too close to safely absorb the blast, while larger gaps aren’t required by the standard and would unnecessarily waste space.

Two inches is the required separation. This clearance keeps the buried mortar tube from contacting the wall of the trough or drum, reducing the chance that the blast or fragments transfer energy directly to the container. It helps contain debris, minimizes heat transfer to the trough wall, and accommodates minor shifts during burial. One inch would be too close to safely absorb the blast, while larger gaps aren’t required by the standard and would unnecessarily waste space.